Capillaries reach into almost all tissues of the human body and supply tissues with oxygen and nutrients as well as removing waste products. Under typical conditions, the endothelial cells lining the capillaries do not divide, and capillaries, therefore, do not normally increase in number or size in a human adult. Under certain normal conditions, however, such as when a tissue is damaged, or during certain parts of the menstrual cycle, the capillaries begin to proliferate rapidly. This process of forming new capillaries from pre-existing blood vessels is known as angiogenesis or neovascularization. See Folkman, J. Scientific American 275, 150–154 (1996). Angiogenesis during wound healing is an example of pathophysiological neovascularization during adult life. During wound healing, the additional capillaries provide a supply of oxygen and nutrients, promote granulation tissue, and aid in waste removal. After termination of the healing process, the capillaries normally regress. Lymboussaki, A. “Vascular Endothelial Growth Factors and their Receptors in Embryos, Adults, and in Tumors” Academic Dissertation, University of Helsinki, Molecular/Cancer Biology Laboratory and Department of Pathology, Haartman Institute, (1999).
Angiogenesis also plays an important role in the growth of cancer cells. It is known that once a nest of cancer cells reaches a certain size, roughly 1 to 2 mm in diameter, the cancer cells must develop a blood supply in order for the tumor to grow larger as diffusion will not be sufficient to supply the cancer cells with enough oxygen and nutrients. Thus, inhibition of angiogenesis is expected to retard or halt the growth of cancer cells.
Receptor tyrosine kinases (RTKs) are transmembrane polypeptides that regulate developmental cell growth and differentiation and remodeling and regeneration of adult tissues. Mustonen, T. et al., J. Cell Biology 129, 895–898 (1995); van der Geer, P. et al. Ann Rev. Cell Biol. 10, 251–337 (1994). Polypeptide ligands known as growth factors, or cytokines, are known to activate RTKs. Signaling of RTKs involves ligand binding and a shift in conformation in the external domain of the receptor resulting in its dimerization. Lymboussaki, A. “Vascular Endothelial Growth Factors and their Receptors in Embryos, Adults, and in Tumors” Academic Dissertation, University of Helsinki, Molecular/Cancer Biology Laboratory and Department of Pathology, Haartman Institute, (1999); Ullrich, A. et al., Cell 61, 203–212 (1990). Binding of the ligand to the RTK results in receptor trans-phosphorylation at specific tyrosine residues and subsequent activation of the catalytic domains for the phosphorylation of cytoplasmic substrates. Id.
Two subfamilies of RTKs are specific to the vascular endothelium. These include the vascular endothelial growth factor (VEGF) subfamily and the Tie receptor subfamily. Class III RTKs include VEGFR-1, VEGFR-2, and VEGFR-3. Shibuya, M. et al., Oncogene 5, 519–525 (1990); Terman, B. et al., Oncogene 6, 1677–1683 (1991); Aprelikova, O. et al., Cancer Res. 52, 746–748 (1992).
Members of the VEGF subfamily have been described as being able to induce vascular permeability and endothelial cell proliferation and further identified as a major inducer of angiogenesis and vasculogenesis. Ferrara, N. et al., Endocrinol. Rev. 18, 4–25 (1997). VEGF is known to specifically bind to RTKs including VEGFR-1 and VEGFR-2. DeVries, C. et al., Science 255, 989–991 (1992); Quinn, T. et al., Proc. Natl. Acad. Sci. 90, 7533–7537 (1993). VEGF stimulates the migration and proliferation of endothelial cells and induces angiogenesis both in vitro and in vivo. Connolly, D. et al., J. Biol. Chem. 264, 20017–20024 (1989); Connolly, D. et al., J. Clin. Invest. 84, 1470–1478 (1989); Ferrara, N. et al., Endocrino. Rew. 18, 4–25 (1997); Leung, D. et al., Science 246, 1306–1309 (1989); Plouet, J. et al., EMBO J 8, 3801–3806 (1989).
Because angiogenesis is known to be critical to the growth of cancer and to be controlled by VEGF and VEGF-RTK, substantial efforts have been undertaken to develop therapeutics that are antagonists of VEGF-RTK to thereby inhibit or retard angiogenesis, and hopefully interfere or stop tumor proliferation.
A wide variety of chemical compounds and compositions have been reported as having activity against one of more the VEGF-RTKs. Examples include quinoline derivatives such as described in WO 98/13350, aminonicotinamide derivatives (see, e.g., WO 01/55114), antisense compounds (see, e.g., WO 01/52904), peptidomimetics (see, e.g., WO 01/52875), quinazoline derivatives (see, e.g., U.S. Pat. No. 6,258,951) monoclonal antibodies (see, e.g., EP 1 086 705 A1), various 5, 10, 15, 20-tetraaryl-porphyrins and 5, 10, 15-triaryl-corroles (see, e.g., WO 00/27379), heterocyclic alkanesulfonic and alkane carboxylic acid derivatives (see, e.g., DE19841985), oxindolylquinazoline derivatives (see, e.g., WO 99/10349), 1,4-diazaanthracine derivatives (see, e.g., U.S. Pat. No. 5,763,441), and cinnoline derivatives (see, e.g., WO 97/34876), and various indazole compounds (see e.g., WO 01/02369 and WO 01/02369).
Various indolyl-substituted compounds have recently been disclosed in WO 01/29025, and various benzimidazolyl compounds have recently been disclosed in WO 01/28993. These compounds are reportedly capable of inhibiting, modulating, and/or regulating signal transduction of both receptor-type and non-receptor tyrosine kinases. Some of the disclosed compounds contain a quinolone fragment bonded to the indolyl or benzimidazolyl group.
The synthesis of 4-hydroxy quinolone and 4-hydroxy quinoline derivatives is disclosed in a number of references. For example, Ukrainets et al. have disclosed the synthesis of 3-(Benzimidazol-2-yl)-4-hydroxy-2-oxo-1,2-dihydroquinoline. Ukrainets, I. et al., Tet. Lett. 42, 7747–7748 (1995); Ukrainets, I. et al., Khimiya Geterotsiklicheskikh Soedinii, 2, 239–241(1992). Ukrainets has also disclosed the synthesis, anticonvulsive and antithyroid activity of other 4-hydroxyquinolones and thio analogs such as 1H-2-oxo-3-(2-benzimidazolyl)-4-hyrdoxyquinoline. Ukrainets, I. et al., Khimiya Geterotsiklicheskikh Soedinii, 1, 105–108 (1993); Ukrainets, I. et al., Khimiya Geterotsiklicheskikh Soedinii, 8, 1105–1108 (1993); Ukrainets, I. et al., Chem. Heterocyclic Comp. 33, 600–604, (1997).
The synthesis of various quinoline derivatives is disclosed in WO 97/48694. These compounds are disclosed as capable of binding to nuclear hormone receptors and being useful for stimulating osteoblast proliferation and bone growth. The compounds are also disclosed as being useful in the treatment or prevention of diseases associated with nuclear hormone receptor families.
Various quinoline derivatives in which the benzene ring of the quinolone is substituted with a sulfur group are disclosed in WO 92/18483. These compounds are disclosed as being useful in pharmaceutical formulations and as medicaments.
Quinolone and coumarin derivatives have been disclosed as having use in a variety of applications unrelated to medicine and pharmaceutical formulations. References that describe the preparation of quinolone derivatives for use in photopolymerizable compositions or for luminescent properties include: U.S. Pat. No. 5,801,212 issued to Okamoto et al.; JP 8-29973; JP 7-43896; JP 6-9952; JP 63-258903; EP 797376; and DE 23 63 459.
Despite the exploration of a variety of chemistries to provide VEGF-RTK-antagonist therapies, a continuing need exists for compounds that inhibit the proliferation of capillaries, inhibit the growth of tumors, and/or inhibit vascular endothelial growth factor receptor tyrosine kinase and pharmaceutical formulations that contain such compounds. A need also exists for methods for administering such compounds and pharmaceutical formulations to patients in need thereof.